Method for making burners



July 7, 1936.

c. HARDWICK METHOD FOR MAKING BURNERS Filed Jan. 2, 1955 3 Sheets-Sheet l July 7, 1936. Q HARDWjQK I 2,046,682

METHOD FOR MAKING BURNERS Filed Jan. 2, 1955 3 Sheets-Sheet 2 July 7, c HARDWICK I METHOD FOR MAKING BURNERS F'iled Jan. 2 1935 5 Sheets-Sheef s Patented July 7, 1936 UNITED STATES METHOD FOR MAKING BURNERS Christopher L. Hardwick, Cleveland, Tenn. Application January 2, 1935, Serial No. 172

3 Claims.

This invention relates to a method of making round cast burners for gas ranges, and has for an object the provision of a new and improved method of this character.

In the drawings accompanying this specification and forming a part of this application:

Figure l is a side elevation partly in section of the apparatus;

Figure 2 is a bottom view of the cutter head with the cutters shown in outer position;

Figure 3 is a vertical sectional view of the apparatus, the cutters being shown in inner position;

Figure 4 is a bottom view of the cutter head with the cutters in inner position;

Figure 5 is a plan view of the cutter actuating mechanism;

Figure 6 is a vertical sectional View through one of the stationary cutters showing the first operation upon the burner;

Figure 7 is a bottom plan view of Figure 6;

Figure 8 is a vertical sectional viewthrough one of the movable cutters showing the position assumed in forming the burner slot and overhang; and

Figure 9 is a bottom plan view of Figure 8.

Referring more particularly to the drawings I denotes a drill press table, and'2 a cast gas burner adapted to be held in stationary position on the table by means of a suitable holder 3. My improved apparatus 4 comprises 'a vertically disposed bored shaft 5, to the lower end of which a cutter head 6 is suitably fixed, the upper end of the shaft being formed with a tapered shank portion 1, adapted to be inserted in and rotated by a chuck 8, forming part of the drill press, not shown. p

The cutter head 5 comprises a circular top plate 9, to the bottom face of which a plurality of spaced guide segments I are secured by screws These parts 9 and II) are also additionally secured together by means of headed studs or bolts l2, one foreach segment, the shank M of which passes through the top plate and segment, and thence through a cutter l3, a nut I4 on the threaded end of the shank being employed to tightly clamp the cutter to the bottom face of the segment. A screw key I5, serves to hold the stud |2 from becoming accidently misplaced when the cutter is removed. The cutter head is secured to the shaft or spindle 5, by means of a reaming tool Is, the upper tapered end of which has a driving fit within the bore of the shaft. A collar pinned to the shaft above the plate 6, and a nut l8 threaded on the lower'reduced end of the shaft 5, serveto removably clamp the parts in place. The lower end of the reamer 6 is tapered and formed with a plurality of flutes to provide cutting edges l9.

Slidably mounted for radial movement between adjacent segments ID are four plates 20, having beveled side edges 2|, engaging with the reversely beveled or under-cut side edges 22; of the segments. These sliding plates carry depending studs 23 upon which upper and lower disk-shaped cutters 24 and 25 respectively are fixedly mounted. Collars 26, one for each stud 23, space the upper cutters 24 from the plate 20, while nuts 21 clamp the two cutters tightly upon the studs. It will be noted that the upper cutters 24 are of greater diameter than the lower cutters 25, for a purpose hereinafter described.

Adjustment of the sliding plates 20 and the cutters carried thereby is effected through the medium of a plurality of arms 28, having a horizontally disposed portion extending into radial. slots 29, in top plate 9, and engaging the top face of the sliding plates, bolts being employed to secure the arms to the plate. The inner ends of the arms 28 are formed with upwardly and inwardly inclined extensions 3| which project into upwardly and inwardly inclined slots 32, formed in a cone shaped member 33, preferably in the form of a casting. The extremity of each extension 3| carries a roller 34, of approximately the same diameter as that of the slots 32. Whenthe casting 33 is lowered from Figure 1 position to Figure 3 position the outer wall or cam face 35 of the slots 32 will act upon the rollers 34, to force the plates and their cutters inwardly and when the casting is moved upwardly from. Figure 3 to Figure 1 position, the inner wall or cam face 36 of the slots will force the plates out- Wardly.

Upward and downward movements of the member 33 are effected by means of a hand wheel 31 and toggle arms 38, four in number. Thus the cam member 33 is formed with a central bore 39 which receives the shaft or spindle 5 for relative vertical movement. A hollow threaded extension 49' integrally formed onthe upper-end of the cam member and having its bore coaxial with the bore 39, projects upwardly through an apertured plate 4|, and is fixed thereto by a nut 42. The bottom face of the plate 4| and the flat top face of the cam member 33 are formed with complemental grooves to provide a race for ball bearings 44 which permit of the plate 4| being easily rotated relatively to the extension 4|]. A second apertured plate 43, similar to but smaller than the plate 4| is rotatably seated above the plate 4|, upon a collar or enlargement 45, fixed to or forming a. part of the shaft 5, and is held against upward vertical movement by a collar 46 threaded upon the shaft. The collar 46 is spaced from the plate 43, similar to the spacing of the plate 4| from the top of the vertically movable cam member 33, and the opposed faces of the collar 45 and the plate 43 are formed with a race for ball bearings 48.

The inner ends of the links 49 of each of the four toggle arms 38, previously referred to, are pivotally connected together by pivot pins 50, and the outer ends of the respective links are pivoted to the plates 4| and 43. Thus pivot pins 5| connect the outer ends of the lower links to vertically disposed flanges 52 extending from end to end of the plate 4|, adjacent the side edges thereof, and the outer ends of the upper links of each toggle arm are pivotally connected to studs 53 projecting laterally from the four corners of the plate 43.

An adjusting screw 54, having a hand wheel 55 fixed to its outer end passes operatively through threaded axially aligned bores 55 and 5'! respectively formed in spaced blocks 58 and 59, for actuating the toggle arms 38. The block 58 is formed with oppositely disposed arms 60, pivotally connected at their inner or free ends to the pivot pins 50, connecting the inner ends of the links 49 of the toggle arms at one end of the plates 4| and 43, while the block 59 is provided with arms 6|, which are pivotally connected at their free ends to those pivot pins 50 of the corresponding toggle arms connected to the opposite ends of plates 4| and 43. The screw threads on that portion of the adjusting screw 54, which actuates the block 58 have a left hand pitch, whereas the portion of the screw which actuates the block 59 has a right hand pitch, to speed up the action of the screw.

A pair of elongated parallel fingers 62 and 63 fixed to and projecting respectively from the plates 4| and 43, are adapted to engage a. post 64 secured to the table I, and prevent the toggle adjusting mechanism from rotating about the axis of the shaft 5.

The operation of the device is as follows: The burner 2, to be operated upon, and which is cast in the general form illustrated in Figure 1 is placed in the holder 3, where it is securely clamped in centered position with respect to the longitudinal axis of the reamer part It? of the tool, by any suitable means not shown. The operator then lowers the rotating chuck 8 and the apparatus carried thereby, with one hand, and guides the reamer into the axial through bore 65 of burner. The rough places in the bore, formed in casting, are thus removed and the bore otherwise trued. At the same time the cutters 3 fixed to the rapidly rotating cutter head 6, machine a perfectly true peripheral portion 66 adjacent the top of the round burner head 2. During this initial operation, the adjustable cutters 24 and 25, fixed to sliding plates 29, remain in Figure 1 or outermost position. 'However, as

the operation of forming the vertically disposed peripheral surface 66 is completed, the operator rotates the hand wheel in a clockwise direction thus causing the blocks 58 and 59 to move in opposing directions. As the blocks separate, the lower ends of the links 49 of each toggle 38 will be forced downwardly, thus communicating similar movement to the plate 4|, which carries the cam 33. Consequently the cam will also be moved downwardly and the sliding plates 20 inwardly in an obvious manner against the expansive action of coil springs 61. As the plates 20 move inwardly the relatively thin cutters 24, which are of greater diameter than the cutters 25, will form a horizontally disposed ring shaped slot 68 in the previously formed surface 66 of the burner. Rotation of the wheel 31 is then continued until the cutters 25, which are of considerable width or thickness engage that portion of the peripheral surface 66, directly beneath the previously formed slot and under-cut the same as at 69, to produce an overhanging portion 10 directly above the slot. The slot 68 constitutes the flame orifice of the burner and the overhanging portion or lip 10 forms a guard for the flame orifice to protect it from becoming clogged by grease or food spilled from a cooking utensil, not shown. Owing to the fact that the cutter 24 is superposed on the cutter 25 and is in overlapping relation with respect to the cutter 25, that is because its cutting portion 1|, extends beyond the cutting portion 12 of the cutter 25, the'slot will be first formed and then the undercut area 69. This insures that the undercut area will extend to the slot and also that burs which both cutters have a tendency to 3 form at the entrance to the slot will be eliminated by the joint and simultaneous action of the coacting portions II and I2, which form a right angle at the top outer extremity of the undercut area 69.

Having thus described my What I claim is:

1. A method of producing a one piece cast burner. having an axial through opening comprising the steps of machining a peripheral surface adjacent the top of the burner head, machining the axial opening, and simultaneously forming a ring shaped slot and overhanging peripheral portion above said slot.

invention:

2. A method of producing a one piece cast burner having an axial through opening comprising the steps of machining a peripheral surface adjacent the top of the burner head, machining the axial opening,-forming a ring shaped slot in said peripheral surface and undercutting said surface directly beneath and at right angles to said slot 3. A method of producing a one piece hollow cast burner comprising the steps of machining a peripheral surface adjacent the top of the burner head, forming a ring shaped slot in said peripheral surface and undercutting that portion of the peripheral surface beneath the slot and at right angles thereto.

CHRISTOPHER L. HARDWICK. 

